Video: Two-thirds of California is still in historically bad drought conditions. Why?

Last year was California's driest year on record yet, and as of right now two-thirds of the state is still in "extreme" to "exceptional" drought conditions, according to the U.S. Drought Monitor.

What exactly is to blame? It is Earth Day after all, so it's worth wondering if climate change is responsible. In truth, there are many complex factors that lead to droughts, and while climate change may be one of them, it's hardly the only factor. In the case of California, the culprit is a ridge of high pressure air off the West Coast of the United States that is four miles high and two thousand miles across. The ridge has been diverting storms that form over the Pacific Ocean away from California and up to Canada.